Re: [PATCH v2 00/21] Refine memblock API

Adam Ford
2019-09-26T19:35:53Z

On Thu, Sep 26, 2019 at 11:04 AM Mike Rapoport <rppt@linux.ibm.com> wrote:
>
> Hi,
>
> On Thu, Sep 26, 2019 at 08:09:52AM -0500, Adam Ford wrote:
> > On Wed, Sep 25, 2019 at 10:17 AM Fabio Estevam <festevam@gmail.com> wrote:
> > >
> > > On Wed, Sep 25, 2019 at 9:17 AM Adam Ford <aford173@gmail.com> wrote:
> > >
> > > > I tried cma=256M and noticed the cma dump at the beginning didn't
> > > > change. Do we need to setup a reserved-memory node like
> > > > imx6ul-ccimx6ulsom.dtsi did?
> > >
> > > I don't think so.
> > >
> > > Were you able to identify what was the exact commit that caused such regression?
> >
> > I was able to narrow it down the 92d12f9544b7 ("memblock: refactor
> > internal allocation functions") that caused the regression with
> > Etnaviv.
>
>
> Can you please test with this change:
>

That appears to have fixed my issue. I am not sure what the impact
is, but is this a safe option?

adam

> diff --git a/mm/memblock.c b/mm/memblock.c
> index 7d4f61a..1f5a0eb 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -1356,9 +1356,6 @@ static phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size,
> align = SMP_CACHE_BYTES;
> }
>
> - if (end > memblock.current_limit)
> - end = memblock.current_limit;
> -
> again:
> found = memblock_find_in_range_node(size, align, start, end, nid,
> flags);
>
> > I also noticed that if I create a reserved memory node as was done one
> > imx6ul-ccimx6ulsom.dtsi the 3D seems to work again, but without it, I
> > was getting errors regardless of the 'cma=256M' or not.
> > I don't have a problem using the reserved memory, but I guess I am not
> > sure what the amount should be. I know for the video decoding 1080p,
> > I have historically used cma=128M, but with the 3D also needing some
> > memory allocation, is that enough or should I use 256M?
> >
> > adam
>
> --
> Sincerely yours,
> Mike.
>